The nurse is caring for a young patient with asthma. Which activity should the nurse encourage in order to help prevent respiratory acidosis?

Correct Answer: A

Rationale: The correct answer is A. Deep-breathing exercises help improve lung function and prevent respiratory acidosis by promoting proper oxygen exchange. This activity can prevent the buildup of carbon dioxide in the lungs, which can lead to respiratory acidosis. Options B, C, and D do not directly address respiratory function and would not be as effective in preventing respiratory acidosis. Drinking fluids, ambulating, or sleeping with the head of the bed elevated can be beneficial for overall health but may not specifically target the prevention of respiratory acidosis in a patient with asthma.

Correct Answer: C

Rationale: The correct answer is C: Kidneys. The kidneys play a crucial role in regulating acid-base balance by excreting or reabsorbing bicarbonate ions and hydrogen ions. They help maintain the body's pH within a normal range. The other choices, A: Lungs, primarily regulate carbon dioxide levels through respiration, while B: Stomach is not directly involved in acid-base balance. D: Brain does not directly participate in compensating for acid-base imbalances.

Correct Answer: A

Rationale: Renin plays a role in blood pressure regulation by activating the renin-angiotensin-aldosterone cascade. Renin is released by the kidneys in response to low blood pressure or low sodium levels. Renin acts on angiotensinogen to form angiotensin I, which is then converted to angiotensin II by angiotensin-converting enzyme. Angiotensin II causes vasoconstriction and stimulates the release of aldosterone, leading to increased sodium and water retention, ultimately increasing blood pressure. Therefore, choice A is correct. Choices B, C, and D are incorrect because renin does not suppress angiotensin production, decrease sodium reabsorption, or inhibit aldosterone release.

Correct Answer: A

Rationale: The correct answer is A because acute kidney injury from postrenal etiology is typically caused by obstruction of urine flow, leading to back pressure in the kidneys. This obstruction can be due to conditions like kidney stones or tumors. Choices B and C refer to pre-renal causes that affect renal blood flow, not obstruct urine flow. Choice D refers to intrinsic renal causes, not postrenal obstruction. Hence, A is the correct answer.

Correct Answer: B

Rationale: The elevated BUN and serum creatinine levels with a normal BUN/creatinine ratio suggest a pre-renal cause, indicating decreased renal perfusion. This is consistent with acute kidney injury (AKI) such as acute tubular necrosis (ATN). In ATN, there is damage to the renal tubules leading to impaired filtration and elevated BUN and creatinine levels. Hypovolemia and fluid resuscitation would typically result in a high BUN/creatinine ratio due to altered reabsorption. Increased nitrogen intake would not lead to elevated creatinine levels. Therefore, choice B is correct as it aligns with the presentation of elevated BUN and creatinine levels with a normal ratio.